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GM LS engine - Generation III

GM LS engine - Generation III: Encyclopedia II - GM LS engine - Generation III

The Generation III small-blocks replaced the LT family in 1997. These shared the same rough displacement and bore spacing (4.4 in) as their cast iron predecessors but almost everything else was changed. The bore was reduced to 3.9 in and the stroke longer at 3.62 in for greater torque. The block was cast from aluminum (for cars) instead of iron and had a new intake and injection technology and coil-on-plug ignition. The traditional five-bolt pentagonal cylinder head pattern was replaced with a square four-bolt design, and the pistons are flat instead of domed. Even the cylinder firing order was changed.See also:

GM LS engine, GM LS engine - Generation III, GM LS engine - LS1, GM LS engine - LS6, GM LS engine - Vortec engines, GM LS engine - Generation IV, GM LS engine - L76, GM LS engine - LS2, GM LS engine - LS4, GM LS engine - LS7

GM LS engine, GM LS engine - Generation III, GM LS engine - Generation IV, GM LS engine - L76, GM LS engine - LS1, GM LS engine - LS2, GM LS engine - LS4, GM LS engine - LS6, GM LS engine - LS7, GM LS engine - Vortec engines, GM Small-Block engine - Generation I, GM LT engine - Generation II, Chevrolet Corvette, LS1 article at AutoSpeed, LS2 article at AutoSpeed

GM LS engine: Encyclopedia II - GM LS engine - Generation III

GM LS engine - Generation III

The Generation III small-blocks replaced the LT family in 1997. These shared the same rough displacement and bore spacing (4.4 in) as their cast iron predecessors but almost everything else was changed. The bore was reduced to 3.9 in and the stroke longer at 3.62 in for greater torque. The block was cast from aluminum (for cars) instead of iron and had a new intake and injection technology and coil-on-plug ignition. The traditional five-bolt pentagonal cylinder head pattern was replaced with a square four-bolt design, and the pistons are flat instead of domed. Even the cylinder firing order was changed.

GM LS engine - LS1

The LS1 was an evolution of the earlier LT small-block V8 but shares little other than similar displacement and external dimensions. It is an all-aluminum 5.7 liter (5665 cc) pushrod engine and produces between 305 and 350 hp (228 to 261 kW) and 375 ft·lbf (508 N·m) of torque, depending on the application. Beginning in 2001, the LS1 received the higher-flowing intake from the LS6, and a smaller camshaft to keep power at the same level; this also allowed GM to remove the EGR system. The block is very similar to that of the higher-output LS6; beginning in 2002, some LS1 engines were actually built using the LS6 block instead. The LS1 was on the Ward's 10 Best Engines list for 1998.

Applications:

1997-2004 C5 Corvette base model
1998-2002 Chevrolet Camaro Z28, SS
1998-2002 Pontiac Firebird Formula and Trans-Am
2004 Pontiac GTO
1999-2005 Holden Commodore as an option
1999-2005 Holden Statesman/Caprice
2001-2005 Holden Monaro

GM LS engine - LS6

LS6 can also refer to a 454 in³ Chevrolet Big-Block engine of the 1970s

The LS6 is a higher-output version of Chevrolet's small-block LS1 engine. It is an all-aluminum 5.7 liter (5665 cc) pushrod engine. The initial 2001 LS6 produced 385 hp (287 kW) and 385 ft·lbf (522 N·m), but the engine was modified for 2002 through 2004 to produce 405 hp (302 kW) and 400 ft·lbf (542 N·m) of torque. The LS6 was originally only used in the high-performance C5 Corvette Z06 model, with the Cadillac CTS V-Series getting the 405 hp engine later. For 2006, the Z06 replaced the LS6 with the new 7.0L LS7.

The LS6 shares its basic block design with the GM LS1 engine, but other changes were made such as windows cast into the block between cylinders. Improved intake, a titanium exhaust, higher-lift cams, and higher compression boosts output, and a new oiling system is better suited to high lateral acceleration.

GM LS engine - Vortec engines

The Vortec 4800, 5300, and 6000 are truck versions of the LS1 engine with different bore and stroke dimensions. The 4.8L and 6.0L versions are iron-block only, while the 5.3L has been built with both iron and aluminum blocks, depending on the application.